(1) Summary of the Invention
The present invention relates to a detector apparatus for measuring wind velocity, direction and/or for measuring ice accumulation or all of these environmental factors. In particular, the present invention relates to a detector apparatus wherein there is no friction between a detecting rod and areas of high stress where the strain is measured, and in its most preferred form uses thin film or foil strain gauges in the area of high stress.
(2) Prior Art
U.S. Pat. No. 3,238,773 to Leigh describes a device which can be used to measure wind velocity. The disclosed apparatus uses a fulcrum to pivot the rod 5 and thus is relatively insensitive. The fulcrum introduces a friction factor which provides variable results, particularly where there are wide temperature variations. There is a suggestion of 360.degree. measurement of wind velocity by the rod 5 but there is no specific discussion of the means for accomplishing this result. The device is not designed to measure weight loads on the rod 5 along the longitudinal axis and no means is provided for removing accumulated ice other than by electrical thawing. the resistance wires of Leigh are relatively insensitive strain gauges.
Most of the prior art devices are designed to detect fluid flow in only one direction in a pipe or conduit as evidenced by the basic disclosure of Leigh and the disclosures of U.S. Pat. Nos. 2,826,914 to Reiley and 3,340,733 to Lasher. None of the apparatus of these references are designed to measure weight loads along the axis perpendicular to the direction of fluid flow.
Other less relevant prior art references are U.S. Pat. Nos. 2,024,571 to Gent, 2,462,577 to Warren, 2,477,233 to Bristol, 2,778,905 to Statham, 2,844,034 to Statham, 2,855,779 to Zaid, 3,114,261 to Dillon et al, 3,147,620 to Stapler, 4,161,118 to Banwell et al, 4,210,021 to Vykhodtsev et al, and 4,499,761 to Plank et al. Generally these patents describe devices which have a single purpose.